Github

With more than 4.5 million users, 1.5 million added in 2013 alone, code collaboration platform GitHub solidified its position as king of open-source software development. Now, thanks to its introduction of "version control"—think Microsoft Word's "track changes" feature, writ large—GitHub wants to banish that blizzard of email attachments that weighs down project-based work in companies. "Teams see how [the coders] are working," says Tim Clem, GitHub's SVP of product, "and they say, 'Hey, why are we not doing that?'" GitHub built several new features to aid this vision: a new repository layout optimized for daily use, better text-editing tools, a mobile site, and new file viewers for noncode documents such as maps and 3-D files.

When GitHub isn't helping its users avoid being bogged down by email, its working on making the web at large a better place. In October 2013, the company launched government.github.com, a website dedicated to showcasing the efforts of local governments around the world. With more than 100 organizations on board already, including NASA, the FCC, and USDA in the U.S., it's making organizations at all levels more accessible.

And in an effort to foster the developer community in all corners of the globe, GitHub teamed with The AfricaHackTrip to sponsor hackathons in four Sub-Saharan African cities. Behind GitHub's initiatives, the web is more open than ever.